Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($) Supplier State Segment	Jun. 30, 2016 USD ($) Segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 30, 2014 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 26,853,000		$ 15,035,000
Allowance for doubtful accounts receivable		$ 1,800,000		900,000
Investment tax credits as percentage of value of eligible solar property		30.00%
Solar energy systems, gross		$ 1,500,286,000		1,064,169,000
Accumulated depreciation and amortization		$ 73,793,000		32,505,000
Property and Equipment, Estimated Useful Lives		30 years
Market capitalization	$ 283,000,000			1,000,000,000
Impairment of goodwill and intangible assets	$ 36,600,000	$ 36,601,000		4,506,000
Amortization period of prepaid tax asset		30 years
Lease term on deferred revenue		20 years
Accrued warranty and home installation reserve, current		$ 800,000		300,000
Accrued warranty and home installation reserve, noncurrent		800,000
Other comprehensive income (loss), net of tax		$ 7,631,000		0
Contractual term of customers		20 years
Description of operating lease agreements		The Company has determined that PPAs should be accounted for as operating leases after evaluating and concluding that none of the following capitalized lease classification criteria are met: no transfer of ownership or bargain purchase option exists at the end of the lease, the lease term is not greater than 75% of the useful life or the present value of minimum lease payments does not exceed 90% of the fair value at lease inception.
Operating leases and incentives		$ 105,353,000		61,150,000	$ 21,688,000
Rebates recognized within operating leases and incentives		500,000		400,000	200,000
Research and development		2,979,000		3,901,000	1,892,000
Advertising costs		$ 2,300,000		4,500,000	3,500,000
Percentage of tax benefit realized upon ultimate settlement		50.00%
Number of reporting segments | Segment		2	2
Total revenue		$ 135,167,000		64,182,000	25,258,000
Sales and marketing expense		41,436,000		48,078,000	21,869,000
General and administrative expense		81,802,000		92,664,000	78,899,000
C&I
Summary Of Significant Accounting Policies [Line Items]
Number of projects initiated | Segment			0
Total revenue			$ 0
Termination fee			$ 1,000,000
Sales and marketing expense		300,000		700,000
General and administrative expense		$ 1,500,000		2,200,000
Financing Obligation
Summary Of Significant Accounting Policies [Line Items]
Service and operational term		5 years
Recognized revenue on investment		0.20%
Investment tax credit rate		30.00%
Solmetric's SunEye and PV Designer Products
Summary Of Significant Accounting Policies [Line Items]
Impairment charges of intangible assets excluding goodwill related to ceased operations		$ 0		4,500,000		$ 0
Internal-use software
Summary Of Significant Accounting Policies [Line Items]
Amortization of internal-use software		$ 800,000		200,000	0
Customer Relationships
Summary Of Significant Accounting Policies [Line Items]
Amortization period of intangible assets		5 years
Trademarks/Trade Names
Summary Of Significant Accounting Policies [Line Items]
Amortization period of intangible assets		10 years
Furniture and Computer and Other Equipment
Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, Estimated Useful Lives		3 years
Solar energy system sales
Summary Of Significant Accounting Policies [Line Items]
Company obligation to customers		$ 400,000		0
Solar Energy Systems
Summary Of Significant Accounting Policies [Line Items]
Solar energy systems, gross		1,532,100,000		1,134,700,000
Power Grid
Summary Of Significant Accounting Policies [Line Items]
Solar energy systems, gross		1,417,400,000		882,700,000
Solar Renewable Energy Certificates
Summary Of Significant Accounting Policies [Line Items]
Operating leases and incentives		$ 19,300,000		$ 13,900,000	$ 2,600,000
Accounts Receivable | Customers | Solar energy system sales
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		64.00%
Cost of Goods Product Line | Solar Photovoltaic Module Purchases
Summary Of Significant Accounting Policies [Line Items]
Number of suppliers | Supplier		3
Cost of Goods Product Line | Inverter Purchases
Summary Of Significant Accounting Policies [Line Items]
Number of suppliers | Supplier		2
Cost of Goods Product Line | Solar Energy Systems
Summary Of Significant Accounting Policies [Line Items]
Number of states customer are located | State		14
Cost of Goods Product Line | Customers | Solar Energy Systems | California
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		31.00%		36.00%	48.00%
Cost of Goods Product Line | Customers | Solar Energy Systems | Northeastern United States
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		35.00%		40.00%	38.00%
Cost of Goods Product Line | Supplier One | Solar Photovoltaic Module Purchases
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		84.00%
Cost of Goods Product Line | Supplier One | Inverter Purchases
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		95.00%
Cost of Goods Product Line | Supplier Three | Solar Photovoltaic Module Purchases
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		84.00%
Cost of Goods Product Line | Supplier Two | Solar Photovoltaic Module Purchases
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		84.00%
Cost of Goods Product Line | Supplier Two | Inverter Purchases
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage		95.00%
Minimum
Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 10,000,000		$ 10,000,000
Product warranty period against defects in design and workmanship		1 year
Warranty period		1 year
Minimum | Developed Technology
Summary Of Significant Accounting Policies [Line Items]
Amortization period of intangible assets		5 years
Minimum | Vehicles
Summary Of Significant Accounting Policies [Line Items]
Vehicles under capital leases, useful life		3 years
Minimum | Leasehold Improvements
Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, Estimated Useful Lives		1 year
Minimum | Solar Energy Systems
Summary Of Significant Accounting Policies [Line Items]
Warranty period		10 years
Minimum | Photovoltaic Installation Software Products and Devices
Summary Of Significant Accounting Policies [Line Items]
Warranty period		6 months
Maximum
Summary Of Significant Accounting Policies [Line Items]
Product warranty period against defects in design and workmanship		20 years
Warranty period		20 years
Maximum | Developed Technology
Summary Of Significant Accounting Policies [Line Items]
Amortization period of intangible assets		8 years
Maximum | Vehicles
Summary Of Significant Accounting Policies [Line Items]
Vehicles under capital leases, useful life		4 years
Maximum | Leasehold Improvements
Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, Estimated Useful Lives		12 years
Maximum | Solar Energy Systems
Summary Of Significant Accounting Policies [Line Items]
Warranty period		25 years
Maximum | Photovoltaic Installation Software Products and Devices
Summary Of Significant Accounting Policies [Line Items]
Warranty period		1 year
Interest Reserve Accounts
Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 16,900,000
Cash and Cash Equivalents
Summary Of Significant Accounting Policies [Line Items]
Maturity of time deposits		3 months